Power-loom



JOHN GRAVSHAV, OF ROCHESTER, NEXV YORK.

POWER-LOOM.

Specification of Letters Patent No. 22,065, dated November 16, 1858..

To all 'whom it 'may concern.:

Be it known that I, JOHN CRAwsHaw, of Rochester, in the county of Monroeand State of New York, have invented certain new and useful Improvementsin Power- Looms; and I do hereby declare that the following is a full,clear, and exact description of the same, reference being had to theaccompanying drawings, forming part of this specification, in which-Figure l is a vertical section of a powerloom, in a plane parallel withthe warp. Fig. 2 is a back elevation of the same. Fig. 3 is a frontelevation of a portion of the same.

Similar letters of reference denote like parts in the three figures.

This invention consists, firstly, in certain means of controlling thetake-up motion of a power-loom, whereby its operation is renderedperfectly uniform.

It consists, secondly, in certain means of governing the let-off motion,whereby the amount of let-off is caused to be always in proportion tothe amount of the take-up.

-To enable others skilled in the art to make and use my invention I willproceed to describe its construction and operation.

A, is the framing of the loom; B, the crank shaft; C, C, the cranks; D,the lay; E, the connecting rods connecting the cranks with the lay todrive it; F, the breast beam; Gr, the yarn beam; and H, the cloth beam.All the above parts are constructed and arranged in a well-known orusual manner, as will be understood by a reference to the drawings.

The cloth beam H, which is furnished with journals fitted to rotate instationary bearings in front of the framing, is furnished at one endwith a spur gear a, which gears with a pinion b, that is fitted to turnon a fixed stud c, secured in the side of the framing. The pinion 5, hassecured to it a ratchet wheel cl, which is engaged by a spring pawl d',secured to the front of the framing; and the stud c has fitted to it,and constitutes the fulcrum of, a lever e, g, one arm e, of whichcarries a pawl f, engaging with said ratchet wheel; and the other arm g,which is bent, has connected with it the upper end of a spiral spring h,the lower end of which connects with the nearly horizontal arm 2', of aright angled lever z', j, 7c, whose nearly vertical arm j, is caused bysaid spring always to press against the back of the cloth beam incontact with the cloth thereon, The lever 2', j, 71:, is made with itsfulcrum 7c, in the form of a rockshaft which is fitted to work inbearings Z, Z, attached to the lower front rail of the framing, in orderthat while the arm e', is at or near the side of the loom, the arm j,may bear upon the cloth-beam near the middle of its length, as shown inFig. 3. The tension of the spring l1, acts upon the lever g, with atendency to press pawl f, against the faces of the teeth of the ratchetwheel d, and hence to turn the ratchet wheel in the direction of theblack arrow shown upon it in Fig. l, and thus cause the cloth beam toturn in the direction of the black arrow shown upon it in the samefigure, and take up the cloth; but to perform the take-up, it isnecessary that the pawl should pass over one or more teeth of theratchet, and this movement of the pawl is effected by means of theaction upon the lever e, g, of a stud or antifriction roller m, attachedto one of the swords of the lay. The above movement of the lever e, g,effected by the stud or roller m, would be greater or less, even to itstotal suspension, according as the tension of the cloth is less orgreater; as said tension acting to press the ratchet back against thepawl j', tends to depress the arm c, and raise the arm g, of the levere, g; and the higher the said arm is raised, the less action will thestud or roller have upon it; and so long as there is a sufficienttension on the cloth, it is not necessary that the stud or roller shallstrike the lever at all. The cloth beam is held while the pawl movesback over the teeth of the ratchet, by the engagement of the pawl fl,with the ratchet-wheel CZ.

Tt must be observed that as the quantity of cloth on the cloth beamincreases, a given degree of tensionowing to the increasing distance ofthe cloth from the center of the roller-has a stronger effect in forcingthe ratchet teeth back against the pawl, and raising the arm g, of thelever e, g; and hence, in order that the take-up may be uniform, thetension of the spring It, should be increased as the quantity of clothon the beam increases.' The lever fi, j, effects such increase oftension, for as the arm j, of said lever is forced back by the increaseof cloth on the beam, the arm z', to which said spring is attached isdepressed. The increase of tension of the spring also produces acorresponding and necessary increase of friction of the arm j, of thelever upon the cloth beam, and hence the action of the take-up must beuniform; it being governed entirely by the tension of the cloth andwarp. The pawl d', must be elastic enough to permit the action abovedescribed. The tension of the warp may be adjusted to make the take-upmotion operate faster or slower by shifting' the connection of thespring farther along the arm e, of the lever e, g.

The yarn beam Gr, has secured to either or each end a drum n, over whichpasses a friction strap o, one end of which is secured to the framing'and the other to a weighted lever 79, which hangs on a fulcrum p,secured in the frame, and is arranged parallel with the back of theloom. The drawing shows a drum, friction strap, and weighted level' ateach end of the yarn beam; as I propose to apply them at each end, toall looms for weaving wide fabrics, though it it sufficient to applythem to one end only of a loom for weaving narrow goods. The weights s,s, which act upon the levers p, p, are not suspended directly from thelevers, but are attached each to one of two other levers q, q, whosefulcrum is a long screw r, which has journals at its extremities fittedto turn in bearings in the ends of the loom frame; said levers p, p,passing through holes in t-he other levers, g, Q One half the length ofthe screw r, has a right-handed and the other half a left-handed thread;and the levers g, g, are tapped to fit the said screw one to theright-handed and the other to the left-handed portion, so that by therevolution of said screw in the proper direction indicated by the arrowsho-wn near it in Fig. 1, both arms may be moved together toward thesides of the loom and thus caused to carry the weights s, s, nearer tothe fulcra of the levers j), y), and hence reduce their effect on thefriction straps o, 0. The screw has secured to it near one end a ratchetwheel t, in which works a pawl fv, attached by a pivot to an arm a,which is secured rigidly to and hangs below what I call a rock-beam,which is a square beam I, occupying the position occupied in other loomsby what is called the whip roll, and furnished at its ends with journalsae, x, fitting' to bearings in the sides of the framing'. The arm u, hasa spring w, applied, which pulls it forward and applies force to thepawl o, in a direction to turn the ratchet wheel in the directionindicated by the arrow last mentioned, and this spring' at the same timeexerts a tendency to hold back the top of the rock-beam against thetension of the yarn which passing over it from the yarn beam in themanner represented in red color in Fig. l, tends to draw it forward.

The let-off motion is controlled so as to correspond with the take-upmotion by the friction of the bands o, 0, upon the drums n, n, which areproperly adjusted at starting' by bringing the weighted levers Q, g,near to or at a suitable distance from the middle of the length of thescrew r. The beating-up of the lay produces a vibrating motion of therock-beam, and when the tension of the warp between the rock-beam andthe filling point at the time the lay strikes the filling, reaches acertain point, the rockbeam carries its arm u, so far back that the pawlo, passes over av tooth of the ratchet wheel; and when the lay comesback, the pull on the rock-beam being reduced, the spring fw, ispermitted to pull forward the arm u, and cause the pawl o, to move theratchet wheel, thus turning the screw in the levers Q, g, and drawing'said levers nearer to the sides of the loom and to the fulcra of thelevers p, p, and reducing the effect of the weights s, s, on thefriction straps o, 0. As the operation of weaving proceeds, the aboveoperation is repeated at short inter" vals of time; and by that means asthe quantity of yarn on the yarn beam is reduced, and the tension on theyarn beam is less effective in turning the said beam, the friction ofthe bands o, o, .is constantly reduced, and if the weights and leversare properly proportioned, the said reduction in friction will beprecisely in proportion to the capacity of the tension on the yarn toturn the yarn beam and effect the letting-off.

I do not claim operating the take-up motion by means of a pawl attachedto a. lever operated upon by a stud or roller attached to the lay. Nordo I claim reducing the friction on the yarn beam as the quantity ofyarn upon it is reduced, by the use of weights traveling along leversconnected with the friction straps. But

What I claim as my invention, and desire to secure by Letters Patent, is

l. The lever z', j, 7c, applied in combination with the cloth roll andwith the spring 7L, of the take-up lever, to operate substantially asherein described for the purpose herein set forth.

2. The rock beam I, its arm u, and pawl fu, applied in combination withthe ratchet wheel t, screw r, and lever or levers g, g, and weight orweights s, substantially as herein described, to move said weightstoward the fulcra of the friction strap levers 7;, j?, as the quantityof yarn on the yarn beam is reduced.

JOHN CRAIVSHAIV. Witnesses:

JN0. C. CHUMAsEno, FRED. DE LAND.

